Traditional radio frequency (RF) front-end modules generally use parallel RF amplifiers. Each RF amplifier amplifies an RF signal formatted in accordance with an RF communication standard or a set of RF communication standards. For example, multimode RF front-end modules may include multiple parallel RF amplifiers to amplify RF signals formatted in accordance with 2G Global System for Mobile Communications (GSM) standards, 3G standards, 4G Long Term Evolution (LTE) standards, and the like. Each of these standards may have various specifications at different frequency bands. For instance, the 2G GSM standard includes a Digital Communication System (DCS) specification; a Personal Communications Service (PCS) specification; a GSM-850 specification; a GSM-900 specification; Enhanced Data Rates for GSM Evolution (EDGE) specifications, such as an EDGE-850 specification, an EDGE-950 specification, an EDGE-1800 specification, or an EDGE-1900 specification; a General Packet Radio Service specification; and/or the like. The 3G standard may include Wideband Code Division Multiple Access (W-CDMA) specifications, Time Division Synchronous Code Division Multiple Access (TD-SCDMA) specifications, a High Speed Packet Access (HSPA) specification, and/or the like. The 4G LTE standard may include 4G LTE specifications such as a Multiple-Input and Multiple-Output (MIMO) specification, and/or the like. These RF communication standards and associated specifications may have different spectral, output power, frequency band, and power management requirements.
There is an ever-increasing demand for RF front-end modules capable of handling as many RF communication standards and specifications as possible. As such, RF front-end modules use multiple parallel RF amplifiers, because generally a single RF amplifier architecture is not capable of providing amplification in accordance with the multitude of RF communication standards and specifications. Unfortunately, the power support circuitry needed to support all of these parallel RF amplifiers can be spatially inefficient and therefore expensive. For example, RF amplification architectures often employ duplicate power control components to control the various parallel RF amplifiers. In addition, some types of RF amplifiers receive supply voltages from RF switching converters. While RF switching converters are power efficient, they can also be very noisy. As a result, power support circuitry is often segregated from the RF amplifiers on a separate die.
What is needed are RF amplifier architectures with more spatially efficient power support circuitry.